This invention relates to a novel process for the construction of electrodes for use in an electrochemical device. More particularly, the invention embraces a process for the construction of low thickness, lightweight fuel cell electrodes comprising an electrocatalyst and hydrophobic binder.
The advantages of lightweight electrodes for use in fuel cells have been recognized. These electrodes essentially comprise an admixture of electrocatalyst and hydrophobic binder deposited on a substrate material such as a porous carbon or metal support, wire mesh or grid. The electrodes are extremely thin, having low internal electrical resistance and furthermore, take up only limited space permitting the construction of highly compact cells having a high energy to volume and energy to weight ratio. One difficulty with these electrodes, however, is obtaining a controlled distribution of electrocatalyst particles with the hydrophobic polymer particles throughout the electrode structure. Further, it is difficult to obtain reproducibility in the electrodes particularly when employing either relatively heavy or light loadings of catalyst.